Copyright | Copyright (C) 2004-2011 John Goerzen |
---|---|
License | BSD-3-Clause |
Stability | provisional |
Portability | portable to platforms supporting binary I\/O |
Safe Haskell | Trustworthy |
Language | Haskell2010 |
This module provides various helpful utilities for dealing with binary input and output.
You can use this module to deal with binary blocks of data as either Strings or lists of Word8. The BinaryConvertible class provides this abstraction.
Wherever you see HVIO, you can transparently substite a regular Handle. This module can work with any HVIO object, however. See System.IO.HVIO for more details.
Versions of MissingH prior 0.11.6 lacked the BinaryConvertible
class
and worked only with Strings and Handles.
Important note: /binary functions are not supported in all Haskell implementations/. Do not import or use this module unless you know you are using an implementation that supports them. At this time, here is the support status:
- GHC 6.2 and above: yes
- GHC 6.x, earlier versions: unknown
- GHC 5.x: no
- nhc98: no
- Hugs: partial (maybe complete; needs more testing)
Non-binary functions may be found in System.IO.
See also: System.IO.BlockIO
Written by John Goerzen, jgoerzen@complete.org
Synopsis
- class (Eq a, Show a) => BinaryConvertible a where
- hBlockCopy :: (HVIO a, HVIO b) => Int -> a -> b -> IO ()
- blockCopy :: Int -> IO ()
- copyFileBlocksToFile :: Int -> FilePath -> FilePath -> IO ()
- hPutBufStr :: (HVIO a, BinaryConvertible b) => a -> [b] -> IO ()
- putBufStr :: BinaryConvertible b => [b] -> IO ()
- hGetBufStr :: (HVIO a, BinaryConvertible b) => a -> Int -> IO [b]
- getBufStr :: BinaryConvertible b => Int -> IO [b]
- hFullGetBufStr :: (HVIO a, BinaryConvertible b) => a -> Int -> IO [b]
- fullGetBufStr :: BinaryConvertible b => Int -> IO [b]
- hGetBlocks :: (HVIO a, BinaryConvertible b) => a -> Int -> IO [[b]]
- getBlocks :: BinaryConvertible b => Int -> IO [[b]]
- hFullGetBlocks :: (HVIO a, BinaryConvertible b) => a -> Int -> IO [[b]]
- fullGetBlocks :: BinaryConvertible b => Int -> IO [[b]]
- readBinaryFile :: FilePath -> IO String
- writeBinaryFile :: FilePath -> String -> IO ()
- hBlockInteract :: (HVIO a, HVIO d, BinaryConvertible b, BinaryConvertible c) => Int -> a -> d -> ([[b]] -> [[c]]) -> IO ()
- blockInteract :: (BinaryConvertible b, BinaryConvertible c) => Int -> ([[b]] -> [[c]]) -> IO ()
- hFullBlockInteract :: (HVIO a, HVIO d, BinaryConvertible b, BinaryConvertible c) => Int -> a -> d -> ([[b]] -> [[c]]) -> IO ()
- fullBlockInteract :: (BinaryConvertible b, BinaryConvertible c) => Int -> ([[b]] -> [[c]]) -> IO ()
Support for different types of blocks
class (Eq a, Show a) => BinaryConvertible a where Source #
Provides support for handling binary blocks with convenient types.
This module provides implementations for Strings and for [Word8] (lists of Word8s).
Instances
BinaryConvertible Char Source # | |
BinaryConvertible Word8 Source # | |
Entire File/Handle Utilities
Opened Handle Data Copying
hBlockCopy :: (HVIO a, HVIO b) => Int -> a -> b -> IO () Source #
Copies everything from the input handle to the output handle using binary blocks of the given size. This was once the following beautiful implementation:
hBlockCopy bs hin hout = hBlockInteract bs hin hout id
(id
is the built-in Haskell function that just returns whatever is given
to it)
In more recent versions of MissingH, it uses a more optimized routine that avoids ever having to convert the binary buffer at all.
blockCopy :: Int -> IO () Source #
Copies from stdin
to stdout
using binary blocks of the given size.
An alias for hBlockCopy
over stdin
and stdout
Disk File Data Copying
copyFileBlocksToFile :: Int -> FilePath -> FilePath -> IO () Source #
Copies one filename to another in binary mode.
Please note that the Unix permission bits on the output file cannot
be set due to a limitation of the Haskell openBinaryFile
function. Therefore, you may need to adjust those bits after the copy
yourself.
This function is implemented using hBlockCopy
internally.
Binary Single-Block I/O
hPutBufStr :: (HVIO a, BinaryConvertible b) => a -> [b] -> IO () Source #
As a wrapper around the standard function hPutBuf
,
this function takes a standard Haskell String
instead of the far less
convenient Ptr a
. The entire contents of the string will be written
as a binary buffer using hPutBuf
. The length of the output will be
the length of the passed String or list.
If it helps, you can thing of this function as being of type
Handle -> String -> IO ()
putBufStr :: BinaryConvertible b => [b] -> IO () Source #
An alias for hPutBufStr
stdout
hGetBufStr :: (HVIO a, BinaryConvertible b) => a -> Int -> IO [b] Source #
Acts a wrapper around the standard function hGetBuf
,
this function returns a standard Haskell String (or [Word8]) instead of
modifying
a 'Ptr a' buffer. The length is the maximum length to read and the
semantice are the same as with hGetBuf
; namely, the empty string
is returned with EOF is reached, and any given read may read fewer
bytes than the given length.
(Actually, it's a wrapper around vGetBuf
)
getBufStr :: BinaryConvertible b => Int -> IO [b] Source #
An alias for hGetBufStr
stdin
hFullGetBufStr :: (HVIO a, BinaryConvertible b) => a -> Int -> IO [b] Source #
Like hGetBufStr
, but guarantees that it will only return fewer than
the requested number of bytes when EOF is encountered.
fullGetBufStr :: BinaryConvertible b => Int -> IO [b] Source #
An alias for hFullGetBufStr
stdin
Binary Multi-Block I/O
hGetBlocks :: (HVIO a, BinaryConvertible b) => a -> Int -> IO [[b]] Source #
An alias for hPutBlocks
stdout
putBlocks :: (BinaryConvertible b) => [[b]] -> IO ()
putBlocks = hPutBlocks stdout
Returns a lazily-evaluated list of all blocks in the input file,
as read by hGetBufStr
. There will be no 0-length block in this list.
The list simply ends at EOF.
getBlocks :: BinaryConvertible b => Int -> IO [[b]] Source #
An alias for hGetBlocks
stdin
hFullGetBlocks :: (HVIO a, BinaryConvertible b) => a -> Int -> IO [[b]] Source #
Same as hGetBlocks
, but using hFullGetBufStr
underneath.
fullGetBlocks :: BinaryConvertible b => Int -> IO [[b]] Source #
An alias for hFullGetBlocks
stdin
Lazy Interaction
readBinaryFile :: FilePath -> IO String Source #
Like the built-in readFile
, but opens the file in binary instead
of text mode.
writeBinaryFile :: FilePath -> String -> IO () Source #
Like the built-in writeFile
, but opens the file in binary instead
of text mode.
Binary Block-based
hBlockInteract :: (HVIO a, HVIO d, BinaryConvertible b, BinaryConvertible c) => Int -> a -> d -> ([[b]] -> [[c]]) -> IO () Source #
Binary block-based interaction. This is useful for scenarios that
take binary blocks, manipulate them in some way, and then write them
out. Take a look at hBlockCopy
for an example. The integer argument
is the size of input binary blocks. This function uses hGetBlocks
internally.
blockInteract :: (BinaryConvertible b, BinaryConvertible c) => Int -> ([[b]] -> [[c]]) -> IO () Source #
An alias for hBlockInteract
over stdin
and stdout
hFullBlockInteract :: (HVIO a, HVIO d, BinaryConvertible b, BinaryConvertible c) => Int -> a -> d -> ([[b]] -> [[c]]) -> IO () Source #
Same as hBlockInteract
, but uses hFullGetBlocks
instead of
hGetBlocks
internally.
fullBlockInteract :: (BinaryConvertible b, BinaryConvertible c) => Int -> ([[b]] -> [[c]]) -> IO () Source #
An alias for hFullBlockInteract
over stdin
and stdout